A Case of the Supernatural
by Anonymonimus
Summary: Sam and Dean fly to London where there are rumours of an uprising of monsters. Details are vague and scarce but the Winchesters need to stop it from getting chaotic and can only do so with the help of the local consulting detective and his partner. Will they manage to work together, despite their differences and opinionated personalities in time to save England from ruin?
1. Chapter 1

**So I wrote this crossover thing for fun :D**

**I'm not exactly sure where I'm going with this or whether I will finish it or not but I'm posting it anyways XP**

**It was strangely fun to write and it's essentially a sort of warm up for writing a pure Supernatural fanfic and not a crossover lol**

**ANyways, if you like and want me to continue, review and fav :D I'll only add a new chapter if this gets 4 reviews minimum ;P**

* * *

The plane descended through the thick ceiling of grey clouds and London could finally be seen for the first time by those boarding it. Sam sat next to the window, his face pressed against it as he marvelled at the sight bellow and slowly began recognizing some famous monuments. A smile slowly spread on his face, excited that he finally had the chance to travel and to England no less. Dean, who sat next to him, was far less enthusiastic. He had downed sleeping pills in order to sleep for most of the ride but they had failed and so he had remained seated, clutching at the arm rests, gaze fixated on the small screen on the bench before him, eagerly waiting to arrive to destination. Now that the plane had begun its descent, his edginess was all the more apparent as he gasped and swore beneath his breath every time there was an unexpected shift.

Sam tore his gaze away from the aerial sight of London to check on his older brother. His smile partially faded, feeling sympathetic and sorry for his brother's suffering but also amused. They had had a different travelling option which Dean had immediately refused and would not be swayed to use – claiming the mode of transportation had a bizarre effect on his body or something of the like. Castiel had nonetheless insisted repeatedly until the day of departure came, he asked one last time, receiving the same answer and vanished. Sam almost felt like rubbing it in Dean's face, but his brother seemed to be suffering enough and the brotherly taunting could wait for a moment.

"You should look outside." Sam suggested, "Now that the clouds are gone there's a really nice view."

"No offence Sammy," Dean gritted out, glaring at the screen before him, "But please shut the hell up."

Sam nearly smiled but resisted the temptation, "I'm serious," he insisted, "It's pretty amazing. You can even see the London Eye from this angle—"

Suddenly there was turbulence and Dean yelped, pressing himself further against his seat as he groaned and cursed all the more. "Can't this goddamn plane just land!?" he growled, smacking the seat.

Almost on cue, the pilot cued his microphone and addressed the passengers in the plane. "Good afternoon ladies and gentlemen," he said with a relaxed tone, "We are just about to touch down at London's International Airport in about fifteen minutes and we are running a bit early. The weather in London is warm yet cloudy and we are looking at an easy descent. We hope you've had an enjoyable flight and hope to see you again on your next journey."

"See, Dean?" Sam said with a small smile, "Just fifteen minutes and you can walk off."

"Oh fuck me…" Dean groaned, gripping the armrests tighter.

* * *

Getting their passports checked as well as picking up their bags had been a rather long task. The airport was so crowded and by the time they found a cab and were finally able to relax, their bodies began giving in to the time change. They were utterly exhausted and nodding off as their driver babbled randomly about many things, mainly the recent local news and something about a famous consulting detective. And just when Sam and Dean thought they were going to close their eyes for good and fall asleep, Castiel happened.

"I see you've finally made it." He said meekly and as monotone as ever.

Sam and Dean jolted at the random appearance whereas the driver nearly got them killed by swerving into oncoming traffic and then back into their respective lane.

"Blimey!" he hissed, glaring at Castiel through the rear-view mirror. "How the bloody hell did you get in? I don't remember seeing you—"

"He was here the entire time." Dean interjected smoothly.

"But I didn't—" the driver insisted, though he was beginning to doubt his early assumptions.

"Yeah, he helped you pack our bags in the trunk." Sam added with a grin, "Don't you remember?"

The charade they had quickly constructed seemed convincing enough and the driver began mumbling an apology before resuming his earlier rant. The rest of the drive from that point on was relatively quiet, Castiel shifting awkwardly in the middle while both Sam and Dean began to doze off again. Things only livened up slightly once they got to their motel and paid the cab driver, finally allowing themselves to discuss privately.

"So why was it we had to come here, Cas?" Dean asked, stopping just next to the door. "Don't you have other people who can take care of whatever problem there is here? I mean, there have to be other hunters—"

"Ironically, there are no hunters in England." Castiel responded, his bleak tone indicating no actual sign of jest.

"What do you mean ironically?" Dean asked.

"Well," Sam answered instead, "The UK is known for its faery tales and myths. Europe is generally home to most of the things we hunt though they're specifically concentrated in England." He then turned to Castiel, "But how are there no hunters?"

"Most hunters inherit the task from their fathers and so on," he explained, "It is a profession older than you can imagine and when the Europeans began to colonise North America, a lot of creatures left and so did hunters to stop them. This eventually resulted in a feeble amount of hunters remaining and they so happened to become prey to the most powerful of beings that decided to remain. It wasn't long before they were all slaughtered."

"So why didn't they just come back?" Dean asked.

"Communication wasn't as easy and fluent as it is now," Castiel said, "Reaching someone so far away could take a year or more and hunters are always on the move. Most didn't know whereas others didn't have the means or will to return. Eventually, the chaos in England slowly steadied and quieted only to be forgotten for years, until now."

"What happened now?" Sam asked.

"Nothing. Yet." Castiel answered gravely, "But I can feel something big coming. The evil creatures inhabiting this country have remained quiet for so long and though we thought nothing of it at first, we now know they were planning something and reaching full capacity of their strength."

"I don't mean to be a downer here," Dean said, "But that's a bit too vague to work with here, Cas. We need more detail than that."

"I wish I could provide them to you," he said regretfully, "But I'm afraid I don't have them."

"Would you happen to have a lead on someone would?" Sam asked.

"There's been a murder, recently." Castiel said and handed them a newspaper which had seemingly just appeared in his hand. "There was a savage murder of a family." He explained as the brothers skimmed through the article. "The bodies were drained of their blood and no drop of it could be found anywhere in the vicinity."

"Vampires?" Dean suggested.

"No," Sam said, pointing at a paragraph, "Says here that other than their sliced wrists, no other markings were found on their bodies."

"Couldn't it have just been a mass suicide then?" Dean said, unconvinced it was something they should handle.

"Seeing as the family was incredibly religious and didn't have any modern ideologies," Castiel said, "It was initially ruled as such."

"What made them change their minds?" Sam asked.

The newspaper's page suddenly turned and half of the page was covered in a large picture of a man wearing an odd hat. He had high cheekbones, a small mouth and pale eyes with a sharp ferocity to them. If Sam hadn't known any better, he would have assumed that he was one of the things meant to be hunted what with the ethereal look of him.

Dean whistled, "Who's the hotshot?" he asked.

"Sherlock Holmes." Sam read beneath the picture, "And the man in the back is his partner, John Watson."

"That man," Castiel said, "reopened the case and, within a month, solved it."

"What? So he knew what monster went after the family and killed it?" Dean asked.

"No." Castiel corrected, "The creature was a goblin that had taken the appearance of a human. He found him and arrested him, but he escaped from prison a few days ago. I believe he is in danger and you must save him."

Dean glanced at the image and then back at the angel, "Why do you want us to save him?" he asked, "I know it's something we do but we would have done it without you demanding it. Is he important?"

"We don't know what's happening here." Castiel reminded, "The most information we have is that the creatures of this country are rallying together for something big and have been saving their forces. This is the first manifestation in hundreds of years of their presence and malice. That man is a genius sleuth and can help us understand what is happening. All you need to do is convince him to help you."

* * *

"Do you feel that, John?" Sherlock asked, his eyes scanning the surroundings of their apartment.

John lifted his eyes from the computer screen and looked around as well, "No…" he said slowly, "Should I? Did you—"

"Oh hush now, John." Sherlock sighed and strutted to the other side of the room, almost excited by something, "I didn't mean physically, I meant emotionally—spiritually."

"Spiritually?" John repeated, raising an eyebrow. It wasn't the first time he thought his flatmate had gone completely mad but he had learned by then that he would never be so lucky.

"I feel a good case coming our way." Sherlock said, taking in a deep breath and grinning as he peered out the window, "It'll be one to remember."

John stared wordlessly at his best friend, pondering Sherlock's behaviour for a brief moment but ultimately deciding that there was no way he would ever understand it. And so he did what he always did, he brushed it off with a sigh, sat back in his chair and agreed. "Of course." He said.


	2. Chapter 2

**Wellllllll**

**My finals are starting and I've been procrastinating like a boss so...yeeeah**

**Anyways, the drill is the same: 4 reviews (minimum) and I'll write/upload another chapter**

**NOW ENJOY!**

* * *

Sam and Dean were incredibly tired, the effects of the time change getting to them as well as the exhaustion of hours of travelling. Though they wanted nothing more than to sleep, they had to leave almost as soon as they settled into their motel room to find a relatively famous man named Sherlock Holmes. Castiel had told them a goblin he had gotten arrested had freed himself from prison and was gunning for the sleuth and so it was the Winchester brothers' job to save him. No time for rest or a minute to relax when the monster could decide to strike at any time.

"I don't think we've ever dealt with a Goblin before." Sam mused as they packed the weapons they would be needing. Castiel had zapped them to their room shortly after having obtained the key.

"Yeah…" Dean slowly realized and halted his movement, "And I don't think dad's journal mentioned one either. So how the hell are we supposed to kill that thing?"

Sam shrugged, "No clue."

Dean sighed deeply, evidently frustrated by the lack of information, "See?" he said to Castiel, visibly angered, "This is why you need to give us as much information as you can before we jump into something."

"Apologies." Castiel said gravely with a light bow of the head, "I had assumed you already knew everything essential. You _are_ hunters."

"We haven't killed at least one of everything, Cas." Dean snapped, "There's a billion species of _things_ out there and not all of them are in America."

"Calm down." Sam sighed. "We'll just call Bobby and have him check everything."

"And what are we supposed to do while he looks for the information?" Dean asked, "We can't just wait here, twirling our thumbs like idiots! That detective guy could be dead by the time we figure everything out."

"We'll just take one of everything." Sam rationalized, "Salt rounds, holy water, a silver dagger, and whatever. If Bobby doesn't contact us by the time the goblin decides to strike then we'll improvise with what we have."

Dean frowned, sighing heavily for a moment before turning back to Castiel, "Next time, just tell us everything." He said before looking through their weapons and selecting what he would carry.

Sam did the same thing and soon enough they were all ready to go. They called Bobby, requested all the information he had on goblins and Castiel then zapped them to the front of the detective's home. Sherlock Holmes lived in an apartment that seemed rather tamed compared to the expectations of the Winchesters. Based off the article they had read in regards to the man, they assumed he would extravagant and posh tastes but his apartment demonstrated the contrary.

It was situated quite narrowly next to a little shop with a red tent sheltering the front entrance and the few seats placed beneath it. The door to Sherlock's home was a dark black with a certain green tint to it surrounded by white bricks. And though the contrast should have made it stand out, it seemed to blend in perfectly with everything rendering it, to a certain degree, invisible. Sam and Dean exchanged glances before turning away as to discuss their strategy with Castiel.

"Any ideas on how to approach this guy?" Dean asked.

"Not really." Sam admitted, a bit puzzled.

There was a moment of silence before Castiel decided to speak, "Well…" he said slowly, "I'll leave this matter to you—"

"Hold it! Hold it!" Dean stopped him just as he was about to leave. Castiel looked back at him, slightly confused, "Where do you think you're going?"

"The monsters plaguing England are planning something." Castiel reminded, "I'm going to try to find out what."

"Well you're going to have to wait a little." Dean said, waving him back to the consensus. "We might need your help with this thing."

"Dean's right." Sam agreed. "We don't know what we're dealing with and if things get hairy, we might need you."

Castiel sighed and reproached the group, keeping his head low, "What do we do then?" he asked.

"What was his job again?" Sam asked.

"Consulting detective." Dean answered, "Like what the hell kind of job is that? It sounds made up."

"The article I read did mention something like that." Sam mumbled but got back to the point, "Anyways, since he's a detective and, according to the newspaper, he doesn't typically work with the police force, he might accept private jobs. We could approach him with a story, claiming help for some reason and get him out of his home. Somewhere safe where the goblin won't find him."

"Sounds good." Dean said, "But we need a story before we waltz in there."

And so they began discussing, slowly forming a concrete lie just on the other side of the road from Sherlock Holmes's house, unaware they were being watched from the very same apartment.

* * *

"There are three blokes on the other side of the road." John said, tilting his head as to get a better look at their faces. "They look rather shady. I don't think they're clients…"

"Oh please John," Sherlock growled, "What would you know?"

John rolled his eyes and stepped away from the window, wandering into the kitchen where the kettle of boiling water whistled loudly. Sherlock had been in a bad mood for the longest time what with being bored without a good case. He was in a slump and so much so that he refused to look at any of the files Lestrade brought them. John had attempted to get him to consider one of them but Sherlock's mind had been set and the ex-soldier knew there was nothing he could do from that point on.

"I think we should call the police." John said as he poured the water into a cup.

"They haven't even committed a crime yet." Sherlock stated, rolling on the couch to find a comfortable position.

"It's just to be safe." John said, dropping a bag of tea in the cup before bringing it to his computer. "It could be one of Moriarty's men."

"Ha!" Sherlock scoffed bitterly, "Don't be daft John. Moriarty would never do such a thing."

"Well you've pissed off a lot of criminals," John snapped, "They could easily be one of their goons."

"Doubtful." Sherlock concluded, lying on his stomach, face buried in a pillow, "And even if you were right – which you aren't – they wouldn't be anything close to a threat. The criminals I deal with on a daily basis are idiotic, foolish and irrational thus easily overpowered and defeated by pure intellect."

John stared at his flatmate quietly, mentally stabbing him before sighing and deciding to end the conversation there. He opened his computer and tipped in the password as soon as the screen flickered on.

"A part of me wishes they were criminals," Sherlock continued, his voice partially muffled by his position, "Things would finally get less boring around here."

Suddenly, there was a ring at the door and both John and Sherlock looked towards it.

"You might get what you wished for." John said, sipping at his cup.

The three men John had seen outside soon entered their flat, led by Ms. Hudson. She was quickly shooed away by Sherlock who had taken an immediate interest to the three guests and urged them to sit down wherever they pleased. Two of them soon introduced themselves as Sam and Dean.

"We heard you were a really great detective." Sam cooed.

"Great?" Sherlock snorted, "That barely does justice."

Sam exchanged a puzzled look with Dean before he continued slowly, "Right," he said, "Well, we need your help."

"Do you?" Sherlock asked sarcastically, immediately noticing how his tone irritated Dean. Though Dean seemed more brawn than brain, he wasn't particularly as idiotic as any other would mistake him to be. Just by the harsh look in his eyes and the slight clenching of hands, Sherlock was able to deduce that he knew he had caught on to their lie.

"We found this guy," he said, gesturing the third member that hadn't been introduced, "He lost his memory and everything and we thought you could help us."

Sherlock remained quiet, he stared at all three faces intently in pure silence. John felt awkward and uncomfortable at the weighing quietness, wondering what exactly was going on in Sherlock's complicated head when he suddenly clapped. It was a slow clap, the dry sound of which resounded through the flat almost irritatingly.

"Bravo." Sherlock said as he rested his hands on his lap, "You're quite the liar, aren't you?"

"He's not lying!" The third member interjected quickly.

Dean frowned, "Save it Cas," he said, glaring at Sherlock, "He's not buying any of this."

"Quite right." Sherlock smiled victoriously, "But I must admit, it was the best attempt I've seen in ages. Now," he continued, leaning back into his chair and snatching the lukewarm cup of tea next to him, "What do you actually want?"

The three strangers remained quiet for a brief moment, exchanging silent information through mere looks before a unanimous nod was made and they all rose at once. Sam and Dean both made an attempt to grab the weapons – poorly hidden, Sherlock thought – in their coats but were immediately stopped by John who had surprisingly been a step ahead of them. The crick of his gun froze all three Americans.

"Not another move or I _will_ shoot." John warned darkly.

"Well done, John." Sherlock smirked, standing from his chair and retreating to the kitchen.

"Now raise your hands above your heads." John demanded with frightening authority.

"Dean—"

"Just do as he says, Cas." Dean groaned, obeying John's command.

"No." Cas refused, earning the barrel of John's gun in a flash, "I don't understand why we don't just tell them the truth."

"Because they won't believe it." Sam said, "Now just do as he says."

"And, gentlemen," Sherlock said returning from the kitchen, finally having thrown out his tea, "What truth might that be?"

"A goblin is threatening your safety." Cas said bluntly, Sam and Dean immediately sighing and cringing at how mad the declaration sounded.

"You're mad." John concluded. "Goblins aren't real."

Sherlock, for a moment, remained quiet, perplexed by the honest look in Cas's face. It was almost as though he was perfectly sane, but that, Sherlock knew, was impossible. "Right." He finally agreed, "And neither are werewolves, vampires and ghosts."

"Wrong." Cas concurred.

"Cas, just stop." Dean hissed, "They're not going to believe you—"

"Wait," Sam said, interrupting his brother, "I have an idea."

"Is that so?" Sherlock asked, unimpressed and yet completely curious.

"Castiel, our friend," Sam explained, "He's an angel."

John grimaced at the odd declaration and turned to Sherlock in puzzlement. "As in, an _actual_ angel?" he asked incredulously.

"Yes," Sam insisted, "And we can prove it."

"How?" John asked.

"Shoot him." Sam said.

The demand was surprising enough to render both British men highly uncomfortable. It was more than evident that all three, but particularly Sam and 'Castiel', had lost their minds.

"Your bullets can't kill him." Dean finally said, breaking the tense silence, "Only an angel blade can and those are hard to come across."

"Do you not hear yourselves talk?" John asked, "You're all completely insane!"

"He's telling the truth." Cas insisted, and then, without much warning, he reached into Sam's pocket, pulled out a dagger and stabbed himself. The blow was straight to the heart and blood did indeed drip from the incision but Cas still stood and showed no signs of pain.

Immediately, the doctor within John kicked in and he threw away his gun, rushing to Cas's side as to treat the wound hastily, but just as he cleared the fabric from his way, the stab mark had already healed only leaving a scar. John stared at it in pure astonishment, Sherlock peeking over his shoulder with the same awestruck expression.

"Impossible…" Sherlock muttered beneath his breath, "That's…there must be a trick…"

"The knife—" John said and snatched it from Cas's grasp to test the blade. He looked dismayed when he found that it wasn't fake and particularly sharp. "Sherlock it's—"

"Quiet, John, I'm thinking!" Sherlock barked immediately and began thinking rapidly of every possibility available to explain what had happened.

"We don't have time for this," Dean growled, "Listen, you idiots, Cas is real, _this_ is real and a Goblin is coming for him!" he then pointed at Sherlock who seemed surprised by the gesture.

"Me?" he repeated, he had never felt more clueless in all his life, "Why me?"

"Because you threw it in jail," Sam explained, he pulled out the newspaper they had been consulting earlier and showed the article, "And now it escaped."

"That's Robert MacDonald from the Bloodless Case." John muttered, eyes widening at the picture of the escaped convict. "And he's a…goblin?"

"Yes, well, according to Cas." Dean answered. "And he's out for blood."

"We have to inform Lestrade—" John said but just as he stepped towards the phone, the door to their flat flew open with a loud bang and in came Robert Macdonald.

His blue eyes had suddenly become yellow and flashed with an animalistic ferocity that chilled Sherlock to the bone. Taken aback by the suddenness, he nearly tripped over the footstool but managed to catch himself just in time to see Sam and Dean pull out two guns and shoot him. Two bullets landed perfectly in his chest and belly but drew no blood as they were filled with salt. Strangely enough, Robert Macdonald released a horrendous screech and beneath that a faint sizzling of burning skin could be heard.

"So he doesn't like the salt," Dean concluded, moving to the goblin's left as Sam moved to his right.

"It doesn't seem particularly effective, though…" Sam concluded. "Any ideas on how to deal with this thing, Cas?"

Suddenly, the temporarily stunned Robert Macdonald snapped back into reality, more angry than ever and immediately lunged for Sam. Sam managed to evade his grip skillfully, noticing his sharp claws in the process and quickly warning his brother. The creature then shot back for a few more swings before it was stunned again by mutual shots from Sam and Dean.

"No." Cas finally answered.

And just at that moment, reality caught up with Sherlock and he was finally able to process what was happening, regardless of how insane it seemed to be. "Iron…" He said in a mumble.

"Iron?" John repeated, incredulously.

Rather than repeat himself, Sherlock dashed for the fireplace and grabbed the fire iron which he promptly stuck through the goblin's heart. He was surprised by the inhuman screech Robert Macdonald had released before his eyes became white and he fell to the floor, lifeless. Then, his normal, human appearance slowly melted away and the figure of a grey, wrinkly goblin was revealed to everyone in the room.

"Hun, iron." Sam concluded with a smirk.

"How did you know that?" Dean asked.

"Faery tales." Sherlock answered, staring at the body in complete awe, "Every child in England knows the lore."

"So does that mean you believe us now?" Cas asked, stepping in.

John and Sherlock exchanged looks, "I suppose when you've eliminated all possibilities, whatever remains, however improbable, must be the truth…"


	3. Chapter 3

**Short chapter, nonetheless, I want to thank those for reviewing :D**

**I don't really respond to you (because you essentially all say the same thing which isn't much of a good excuse) even though I should but I want you to know that I do read them and I'm really glad you're all enjoying this.**

**Anyways, the rule is still the same. 4 reviews for the next chapter.**

**ENJOY!**

* * *

The flat was trashed. The front door was barely hanging on its hinges and the goblin had made a nice mess of tearing down the neighbouring furniture. However, what bothered John most out of the entire ordeal was the goblin blood caking the surroundings and the fact that they now had to get rid of a body.

"I guess since you believe us," Sam said, a glint of hope in his tone, "You won't be calling the cops then?"

"Cops?" John repeated, perplexed.

"Well," Sam mumbled gesturing the dead goblin with the barrel of his gun, "Because of that."

"I wouldn't think the police would arrest you for saving our lives." John stated with a kind smile. "But I suppose that we do need to call them…"

"You can't." Dean stated quickly, earning a surprised look from both Brits.

"And why not?" Sherlock asked, "They'll want to know what came of the escaped convict: Robert Macdonald."

"They _can't_ know." Sam said, "The world isn't ready to learn of these things."

"No offence but who are you to decide that?" John asked, folding his arms over his chest.

"I suppose it makes sense." Sherlock concluded with a huff, "Considering that the world is at the brink of chaos yet again, if it were to be known that magical entities are in fact real the world powers would seek to use them as weapons of mass destruction. The other logical outcome would be their extinction which would be deplorable to some extent."

"I don't know," Dean mumbled, "It would make life a lot easier for us if they just disappeared."

Sherlock stared at Dean contemplatively, John assumed he was 'reading' him as he did to everyone they met. "You do this for a living, don't you?" he concluded.

"Bingo," Dean smirked, "And not just us, there are a lot of other hunters out there."

"You can't be serious." John sighed in disbelief.

"Look at the facts, John," Sherlock said snappily, "We have a dead goblin on the floor and a man who heals remarkably fast from stab wounds just next to him."

"But that would mean…" John paled as he came to terms with the conclusions of the evidence before him, "That everything…trolls, goblins, faeries, angels and demons…they're all real…"

Seeing as John was on the brink of fainting, he was quickly redirected to a nearby chair and given a glass of water to help digest the revelation. Sherlock sighed at his weakness and muttered something about how people were so dramatic. John glared daggers at him, having caught most of the mumble.

"Anyways," Sam concluded, "We should get going."

"Wait." Sherlock stopped them immediately. "Why are you here?"

"What do you mean?" Dean asked.

"Why are American supernatural hunters in England?" Sherlock asked, "Shouldn't there be a few already here?"

"Britain hasn't been host to hunters for over two centuries." Cas answered meekly. "We came because no one else would."

"Something big is happening, then?" John asked, sipping at his cup of water.

"Yes." Cas confirmed.

"But don't worry, we'll stop it." Dean smirked.

The three then left, returning back to wherever they decided to reside leaving Sherlock and John with a mess and a dead body.

"What do we do with it?" John asked.

"Burn it, I suppose." Sherlock muttered.

"Shouldn't we call Lestrade?" John asked.

"There wouldn't be much point to it." Sherlock stated, "Even with the evidence staring at him right in the face, he wouldn't believe us."

And so they carried the body to the kitchen, chopping off its limbs with a meat clever and fed it to the fire in their fireplace. It took many hours before the body was reduced to ashes and a few clever lies to keep Ms Hudson in the dark. As they stared at the last piece of the goblin being devoured by fire, both Sherlock and John shared the eerie sensation that an odd case was just around the corner.

* * *

"There's something about him…" Cas mused as he stared out the window of the motel, "I don't quite know what it is…but I think he's going to be important."

"Who? Sherlock?" Sam asked.

"_Sherlock_." Dean repeated with mockery, "Who calls their kid Sherlock? I bet he's the son of some spiffy, rich family or something."

"Do you think he's a prophet?" Sam asked.

"No." the angel replied, "His name isn't among the list. He's not even anyone significantly important to the fate of the world."

"But you think he's important." Sam said, as puzzled as Cas in regards to the ordeal.

"I'm going to go gather some information." Cas declared.

"Hey—"

But he was already gone.

Sam and Dean exchanged looks before returning their gazes to where Castiel once stood. They would obviously be staying in London for far longer than either wanted but what peeved them the most was that Castiel had neglected to tell them their goal. As it was, they were tired and had completed the only job the angel had mentioned before vanishing and in record time at that seeing as the sun hadn't yet begun to set.

"Well…" Sam said, "You want to go visit the city?"

Dean's snoring had been a good enough answer. He was sprawled on his bed, half of his things pouring out of his duffle bag as though a sleep spell had hit him in the midst of unpacking. Sam smirked and scribbled on a notepad left on the nightstand separating their beds what he would be doing and approximately when he would return. Then, he left.


	4. Chapter 4

**Sorry for the delay in posting the next chapter lol XP**

**I lost track of many things but this chapter has actually been done for quite a while lol**

**Anyhow, I don't have much else to say so ENJOY! :D**

* * *

Three days had passed since their encounter with Sherlock. Castiel was still nowhere to be found and the Winchester brothers had finally accommodated themselves to the time change. They had taken the opportunity to explore the foreign city and enjoy what time they could before the angel's return. However, the lack of news on Castiel's part began to inspire worry and the brothers soon found themselves restless and unable to relish the simple pleasures of vacation.

"God damn it." Dean muttered, stepping out of the coffee shop and handing Sam his drink, "What the hell do you think he could be doing?"

"Who? Cas?" Sam asked, sipping at his hot beverage.

"No the fuckin' pope." Dean said sarcastically, rolling his eyes, "Of course I mean I Cas. Like would it kill the guy to just give us a call or an update?"

"You sound like his girlfriend." Sam snickered as they began walking down the street.

"Shut up, you're worried too." Dean growled.

"Yeah but I know he's okay." Sam said with a playful smile, "I mean, he's an angel and he's definitely not easy to kill."

Dean didn't say anything. He accepted Sam's reasoning and decided to leave his complaining at that, knowing that Castiel wouldn't return any faster if he kept it going. "I still don't have to like it." He concluded.

The boys walked for a bit more before coming across a large crowd and police cars. They were all gathered around the perimeter of whatever they were trying to see and many cops were trying to usher them away. Out of mere curiosity but also because neither of them had a better idea of what to do, they pushed through to see what all the fuss is about.

"Sirs, please vacate the area." An officer told them as they stretched their necks to see the scene they were trying to block. "There's nothing to see here—"

"That's not true! Look!" A woman standing next to them exclaimed and she pointed to the left, "It's _Sherlock Holmes_! There's been a murder!"

Sam and Dean exchanged looks but their silent conversation was cut rather short when the people in the back began to shove them in order to see the famous consulting detective. They managed to push their way out of the chaos and separate themselves far enough from the crowd to talk in all seriousness without risk of someone eavesdropping.

"Do you think it's a goblin or whatever else they have here?" Sam asked.

"I don't know…" Dean mumbled, "Should we even check it out? I mean, murders aren't exactly out of the ordinary…"

"And Sherlock's job is to solve crimes…" Sam reasoned as well, "So it doesn't necessarily mean something supernatural is involved."

"Right." Dean nodded, "So I guess we just let it play it out and, tomorrow, we'll check the newspaper and if there's no mention of anything strange, we move on and keep waiting for Cas."

"Alright." Sam agreed.

And so the two left the scene, a part of them hoping it was a monster of some sort. Adventuring a foreign and reputed city was fun and all, but Hunting was their calling and it always felt strange to relax for too long.

* * *

"Sherlock…" John called as he trailed after the taller man, "I think I saw them…"

"Who?" Sherlock asked dismissively as he began hovering over the corpse.

"The Americans, Sam and…whatever his name was." John muttered as he thought, "Danny, Daniel…_Dean_! I think I saw them in the crowd."

"Really now?" Sherlock asked, straightening himself and peering over at the gathering along the perimeter. "I don't see them."

"Maybe they left." John suggested with a shrug. "In any case, if they _were_ there then that would mean…"

"Yes." Sherlock said, understanding the insinuation. "And even if they hadn't been present, it would still be an option now."

"What are you blokes talking about?" Lestrade asked as he approached the two.

"Irrelevant." Sherlock declared and reached down to unsheathe the victim. He grimaced at the sight of her. The victim had been trampled to death in a most gruesome way. The bones in her limbs had been crushed first and she had been kept alive for as long as possible before the final fatal blows were delivered.

"Honestly," Lestrade said after a moment, "Everything points to a horse having done it. However, we've checked everywhere and no farms or zoos have reported a missing horse and even then it would have been impossible for it to have travelled this far deep in London without anyone noticing. So our next guess is a carriage driver gone rogue and murderous."

"Wrong." Sherlock concluded bluntly and left the corpse, "There are no marks on the ground to indicate that one had passed through during that time. In addition, if you don't find dung within a decent circumference of the crime scene, it will further disprove your thesis."

"Well what the bloody hell is it supposed to be?" Lestrade snapped.

"I don't know." Sherlock said dryly but John immediately noticed unrest. The detective began moving to the apartment crowded with more police officers. "I assume there's something else in the house?"

"Yeah." Lestrade said, following Sherlock.

John trailed after them once he had carefully examined the corpse as well. One thing that immediately hit him was the blood. Though there seemed to be a lot surrounding the victim, there typically would have been more especially considering the severity of the wounds and the time it took to find the body. Seeing as it also hadn't been moved, the wounds hadn't been treated to contain or stop the blood flow. By the looks of it, John would assume she was missing at least three pints of blood. The last peculiar thing John noticed as he left the body were these odd bits of flesh that seemed out of place. He couldn't quite tell much what with them being covered in blood and far too revolting to touch, but he was fairly certain they were rotten.

So far, John was almost ready to class the current murder as the most gruesome he and Sherlock had ever encountered until he had seen the condition of the apartment. Everything was perfectly intact and clean until he reached the kitchen. Four bodies, a man and three boys, were lying face down in a puddle of their own blood which also, for the most part, seemed missing. What made things all the worse was the message painted on the ceiling above: "Madison".

"I've seen enough." Sherlock concluded seconds later.

John and Lestrade were both surprised by how little time he had spent in the area but then reckoned the gore had probably finally gotten to him. John immediately chased after him whereas Lestrade decided to give them space.

"Sherlock—" John said as they found a rather secluded area within the perimeter of the crime scene. John paused upon seeing how strangely pale Sherlock had become. "Sherlock…?"

"The world's going mad, John." He muttered quickly. "Trolls, goblins and vampires are suddenly real, how is that remotely normal?"

"I-I…" John stuttered helplessly, "What's wrong?"

"Tell me," Sherlock said dismissively, "What did you noticed in regards to the trampled woman?"

"W-well," John said slowly and shifted in place, "Her limbs were crushed first so she felt a substantial amount of pain before finally dying…and about three pints of her blood were missing."

"What else?" Sherlock insisted.

John didn't know to add until he remembered the odd bits of rotten flesh, "There were pieces of flesh," he said, "And they weren't hers."

"They were rotten." Sherlock specified, "And it was horse meat."

John blinked in shock at the affirmation, he barely had time to dabble on the thought any more before Sherlock pelted him with new questions.

"Moving on to the second part," he said hastily, "What did you notice?"

"More blood seemed to be missing." John said, "Everything was clean and perfect until we reached the kitchen and a name was written on the ceiling."

"What else?" He insisted again.

"Nothing else." John said, "You didn't give me enough time to look around."

Sherlock rolled his eyes and sighed, "The _plants_, John!" he snapped, "They were dead, wilted and rotten. And if you look at the shrubberies standing next to the door, you'll see that they are also as lifeless as the others."

John looked at the shrubbery to confirm what Sherlock had declared and said: "What do you think did this?"

"It wasn't human." Sherlock said gravely, "And it wasn't alone."

"Hypothesis?" John probed.

"A nuckelavee." Sherlock answered, "A creature resembling a centaur but with rotten flesh and, in some legends, legs with fins. Supposedly they're from Scotland and are responsible for ruined crops, epidemics and droughts. They live only to make it Hell for the humans residing nearby. Their breath is so dreadful and riddled with sickness that it can wilt crops and sicken livestock."

"Do you realize how mad this all sounds?" John asked after a moment.

"Of course I do, John!" Sherlock snapped again, "But no human could have done this carnage! There were also no witnesses!"

"You don't know that—"

"Oh come on, John!" Sherlock growled, throwing his arms in the air, "If Lestrade had a witness or two he would have mentioned them! So if we assess what we know, a supernatural culprit is the only explanation."

"So what now?" John asked, frustrated, "We send Scotland Yard after a rotten centaur?"

"I don't know…" Sherlock sighed, and for the first time, he really didn't know what to do.

"What about the second offender?" John asked instead, "You said two creatures had done this."

"A vampire or something of the like." Sherlock said, "It would explain the missing blood seeing as nuckelavee aren't exactly known for consuming blood."

John sighed heavily and slapped a hand on his forehead in exasperation as he thought of how they could deal with the situation. "They're expecting you to tell them something." John said.

"I know." Sherlock said. "I suppose I'll just tell them I won't be taking the case."

"Right and what if they get killed by these things?" John asked angrily, "We have to do _something_, Sherlock."

"I don't know if you've noticed, John," Sherlock barked, "But I'm not exactly known for arresting or intercepting fantasy creatures!"

"Then we'll call Sam and Daniel—Dean to help us." John suggested, at a lost. "We can't leave this as it is and this is our home. We have to contribute to some extent to protect it."

"Everything's gone bloody mad." Sherlock hissed and began to walk away from the scene, "Fine. But I don't want Scotland Yard to get involved in this."


	5. Chapter 5

Sam and Dean had spent the rest of the day leisurely walking about the streets of London. They visited shops and bought clothes here and there, wasting time in tourist areas when they grew bored of what they had initially been doing. Sam found more interest than Dean in visiting certain historical sites such as Churchill's bunker or the Benjamin Franklin house. Nonetheless, the murder they had crossed paths with at the beginning of the day remained at the back of their minds.

Sherlock's job was to solve murders – particularly those with which the Scotland Yard had difficulties. Seeing him at the given crime scene earlier didn't necessarily mean a supernatural creature had attacked. And yet, the brothers couldn't help but remember Castiel stating that the creatures of England were stirring and something big was coming. Furthermore, the angel had added that – though Sherlock's name wasn't mentioned as an important soul to the fate of the world – he was and would be important to the outcome of whatever was happening. In sum, so many facts kept the Winchesters restless and neither were even mildly surprise when a knock came at their door later that night.

They had initially been cautious. Word seemed to travel fast among the monster community and though they hadn't done much work abroad, Sam and Dean were definitely to be reckoned with and taken seriously by the mystical inhabitants. They readied their weapons, Dean gripping a silver blade whereas Sam wielded a loaded gun as the former carefully opened the door. Dean peaked through the small crack and paused for a moment, seemingly confused on who awaited on the other side.

"What is it?" Sam asked, clutching his gun a tad more tightly.

Dean looked back, his surprise and confusion blatantly evident as he opened the door wider, revealing John and Sherlock. John seemed a bit more humble than his partner, apparently wanting to have waited for permission to enter while Sherlock strode in as though it wasn't even mildly impolite. He followed in meekly, keeping his head down almost as though to camouflage his embarrassment and waited to be offered a seat before sitting while Sherlock had taken the liberty of making himself comfortable.

"Uhh…" Sam said slowly, alternating his gaze from his brother to the British guests, "Hi…?"

"Why are you here?" Dean said, freely displaying his weapon as he sat on the foot of his bed.

"Sorry for the intrusion," John began, looking over at Sherlock nervously – he was reading the brothers yet again, "But we need your help."

"With what?" Sam asked, though a part of him already knew the answer, "And how did you find us?"

"It wasn't particularly difficult." Sherlock brushed aside as though it was nothing, "Many signs pointed to neither of you being rich and having extravagant tastes. In addition, what with your claimed profession, it wasn't a far leap to deduce that you both traveled a lot and so preferred to deal with more questionable places so as to efficiently cover your trails if need be and buy the silence of clerks with greater ease. This specific location seemed to accommodate your needs flawlessly in every single way possible."

"Whoa." Dean said, dumbfounded.

"That's amazing." Sam cooed.

"Child's play, really." Sherlock assured as he pulled a folder out of his coat, "Now for the business at hand…" he threw the folder open on the coffee table, revealing images of the murder, reports made by officers on the scene and a detailed yet hasty analysis on the autopsies made. Sam moved closer, setting his gun aside, and gathered the documents, skimming through them, while Dean looked at the pictures. "This morning," Sherlock explained, "We received a call from Scotland Yard to assist in the murder of the Hathaway family. They believe some seriously troubled _human_ cut-throat is the culprit however, due to the new information acquired about the world, we easily deduced that that was not the case."

"Why?" Dean asked, squinting at one of the pictures, "Seems like a horse trampled that one lady to death—"

"He's as daft as Lestrade—"

"Sherlock!" John snapped, kicking his friend and sending him a dirty look, "The Yard thought as much but no horse-drawn carriages patrol that specific area and no horse has been reported missing or escaped. Even so, it would have been spotted by many others before finally reaching the area of the murder and no calls have been made to indicate said possibility."

"Look at that," Sam said, pointing at an aspect of the photograph Dean held, "The plants are dead. Some powerful and evil entities are known to make things rot."

"That doesn't mean anything," Dean stated, "Maybe the Hathaways didn't know how to take care of them properly."

"But look at the ones indoors." Sam insisted, shuffling through them, "They're also dead. If they really failed at taking care of them, they would have thrown them out long ago."

"I guess," Dean shrugged but then revealed the photograph of the bloody kitchen, "But _this_ looks like the work of your typical murderer – just, maybe a bit sloppier than usual."

"There's Madison written on the ceiling in blood," Sam stated, "I guess that can still fall in the hands of a human culprit but didn't the Bloody Mary ghost do something like that? She wrote the names of the victims her victims murdered in blood behind the mirror."

"Bloody—" John repeated in shock, "Did he just say _Bloody Mary_?"

"Yeah," Sam confirmed, "Long story."

"We ganked that bitch," Dean reminded, "It can't be her."

"But it can be something alike." Sam stated. "I mean, these little brands or taunts left behind aren't exactly exclusive to one species."

"We've done research of our own," Sherlock finally said, "I looked into _Madison_ and found that she was Mister Hathaway's previous wife. She killed herself a year after her marriage to him and, soon after, he remarried. He used to beat her and though she sought help, it was never given to her."

"That's the perfect recipe for an angry spirit." Sam stated.

"Alright," Dean ceded, "Then that's what we're dealing with."

"Not quite." John said, "You see, Sherlock quickly noticed that there were two culprits to the whole matter. The trampled woman is the second wife of Mister Hathaway. We found bits of rotten flesh – horse flesh – around her corpse and about three pints of her blood was missing. The same also went with the family murdered in the kitchen."

"Doesn't sound like your typical ghost." Dean admitted.

"What do you think it is?" Sam asked, "Assuming you looked into that."

"The first is a nuckelavee." Sherlock said, "A rotten fusion of a horse and a man hailing from Scotland. They exist merely to make the lives of humans a living Hell and their breath is supposedly so dreadful it can wilt crops and sicken livestock."

"That would explain the woman," Sam nodded, "And the rotten plants."

"What about the missing blood and Madison?" Dean asked, admittedly surprised by the competence of Sherlock and John who had so recently learned the truth about monsters.

"At first," John explained, "We thought it was a vampire. However, those aren't typically found in England so we decided to look for a local variation or simply a similar one."

"Not to mention a vampire wouldn't have let all that blood go to waste." Sam nodded approvingly.

"We found that it could be a Dearg-due." John continued, "It's very similar to a vampire though it also has qualities of the undead. They can suck the life-energy out of a being and they have a taste for blood which would explain the missing pints. They're also known for holding nasty grudges against the family members that have wronged them."

"How are they born?" Dean asked.

"The information was a bit flimsy in those regards," John stated, "Generally, however, they seemed to be born out of rage, hate, misery and jealousy. We found many stories about them and Madison's mimics them to the letter."

"What do you mean?" Sam asked.

"Madison was originally from a poor family," Sherlock explained, "They were desperate for money and so they married her off to an abusive rich man, mister Hathaway. However, Madison was also in love with another man – one Mark Fitzgerald – but her farther forbade them from ever seeing each other again and so their romance ended as such. She eventually killed herself a year after her marriage to mister Hathaway, as previously explained, due to the police's lack of response in regards to her complaints against her violent husband. Her husband remarried almost a month after she passed away and her entire family was murdered exactly a year after her suicide."

"Wow," Dean said, taking the picture of Madison within the folder, "Poor girl."

"It looks like you've pretty much figured everything out." Sam commented, putting the documents back into the file, "I don't understand why you need our help."

"We need to kill them." John said.

"Figuring that out isn't particularly hard." Dean commented.

"Well, we know how to kill the Dearg-due," John said, "But we have no idea how to deal with the nuckelavee."

"Neither do we." Dean said, "This is literally the first time I hear about either of those things."

"Don't you have some sort of archive?" Sherlock asked, "I'm assuming that you supernatural-Hunters write down the things you notice and discover about these creatures for future references."

"Here's the problem with that," Sam explained, "There haven't been any Hunters in Europe ever since the colonization of America. They all left to pursue the monsters there and those who stayed behind eventually died out. We have virtually no information on monsters indigenous to the area unless if they're relatively famous."

"Then how are we supposed to deal with these things?" John asked, dismayed.

"Wait!" Dean exclaimed, "I know! The angel blade!"

"_Angel blade_?" John repeated.

"It's this super OP weapon that can kill anything." Dean explained, "So far, it's literally been able to kill everything except arch-demons and leviathans."

"Alright, where do we get one?" John asked.

"You can't exactly _get_ one." Sam explained, "Only angels are allowed to have them and, after the fiasco we dealt with back home, Cas vetoed all of the ones Hunters and monsters managed to acquire. He's the only one out of all of us who has one."

"And he's missing." Dean remembered angrily. "Damn it! Where's that idiot when you need him?"

"Then what do you suppose we do of the nuckelavee and dearg-gue?" Sherlock asked, "You've been in this profession for quite some time, you must know some alternative."

"Well," Dean said pensively, "You know how to kill the dearg-due so we can deal with that but I literally have no idea on what to do with the nuckelavee."

"We'll have to do research," Sam said, "Find anthropology, history and folklore teachers and experts and scavenge libraries for more information. It could take a while."

"I hate it when we can't use the internet." Dean groaned.

"We, apparently, don't have much of a choice." Sherlock said, "I'll go to the library and find books on the matter, John," he paused briefly and looked at his friend, "Didn't you date a history professor?"

"Yes," John sighed, "Her name was—"

"Irrelevant." Sherlock quickly interrupted, "Go pay her a visit, charm her or whatever and ask for clarifications."

"We'll tag along." Sam declared, "You're new at this and, even if you're doing a good job, I'd feel better if you had professional supervision."

"Very well—"

"Awesome," Dean said quickly, "I'll go to Uni with Watson over there and you can go to the library with Sherlock, Sam."

Sam sighed at Dean's evident attempt at avoiding the most boring of tasks. Nonetheless, he ceded to his elder brother's desire and so they arranged a meeting time and place to get to work the next day. The final thing they exchanged to one another that day was a piece of advice the Winchesters were adamant in sharing: "Folklore and legends vary but that doesn't necessarily mean any of them know or tell of the actual way to deal with monsters."

* * *

**I saw, for the SuperLock crossover, that people tend to pair Sam and John and Sherlock and Dean (as friends not as lovers) which is something I never understood XD **

**In my opinion Sam and Sherlock should be together and John with Dean. Sam is essentially like John in the sense where he's very human and intelligent (maybe even more than John) so Sherlock would probably be more comfortable with him than with Dean who is really immature (albeit smart) since, I think, Sherlock would lose patience with him. I also think that John and Dean have a compatible personality and have lived through similar experiences and so would be able to relate better. **

**But, in any case, my headcannon is still John getting along with both of the boys and Sherlock only liking Sam and picking on John XP**


End file.
